1. Field of Art
This invention relates to automatic cleaners for swimming pools and apparatus for use therewith.
2. Description of Prior Art
Pool cleaners which automatically traverse the floor of a pool to clean the same are well known. These cleaners generally include a head mounted on a pad, feet or wheels and are connected via a suction pipe and flexible hose to a remote pump of a water recirculation system including filters to remove dirt and other debris from the pool water. Water is drawn through a flow channel formed in the cleaner head in communication with the suction pipe and movement of this flow of water through the flow channel is employed to impart motion to one or more devices which operate to cause the cleaner to traverse the pool floor.
In one particular type of automatic pool cleaner, movement of the water through the cleaner head induces a vibratory or pulsating movement to the head substantially in line with the cleaner""s suction pipe. These pulses occur several times per second and impart vibratory movements to the suction pipe and the hose. An example of this type of automatic cleaner is disclosed in EP-A-0543387. Another type of automatic cleaner has a head mounted mini turbine which is driven by water as it is drawn through the flow channel by the pump. The turbine operates flaps or feet which propel the cleaner along the pool floor. An example of this type of cleaner is disclosed in GB-A-2181339.
One major problem with automatic cleaners is a tendency for them to become trapped in pool corners or by pool steps or wall fittings. When this happens the cleaners are unable to change direction. Their cleaning action is therefore discontinued.
An additional problem is that the hose often restricts movements to a series of eclipses or Figures of eight; when this occurs, areas of pools are uncleaned.
The present invention sets out to provide apparatus which overcomes or at least alleviates these problems.
According to the present invention in one aspect there is provided apparatus for use with automatic pool cleaners, the apparatus including a tube which defines flow channel for water drawn from the pool through a hose by a remote pump, the apparatus being characterised in that the tube includes an upper tubular section to which the hose is connected, a lower tubular section connected through a pivot to the upper tubular section, and a tubular ball joint through which water drawn from the pool passes from the lower tubular section to the upper tubular section and about which the upper tubular section can move relative to the lower tubular section, and means connected to the upper tubular section for periodically imparting movement to the upper tubular section thereby to move the upper tubular section and the hose connected thereto between first and second angularly displaced positions.
The joint may be an articulated joint.